[RFR] Add <ma-filtered-list-button> directive

[fzaninotto]

A reusable directive to automatically link to a prefiltered list.

Usage:

post.editionView()
    .fields([
        nga.field('comments', 'referenced_list')
            .targetEntity(comment)
            .targetReferenceField('post_id')
            .targetFields([
                nga.field('id'),
                nga.field('body').label('Comment')
            ]),
        nga.field('', 'template').label('')
            .template('<ma-filtered-list-button entity-name="comments" filter="{ post_id: entry.values.id }" size="sm">')

Refs #338

[fzaninotto]

I'm wondering about the syntax. It would be more powerful to accept a filter object:

<ma-filtered-list-button entity-name="comments" filter="{ post_id: entry.values.id }" text="" size="sm"></ma-filtered-list-button>

What do you think?

[jeromemacias]

I'm 👍 for the filter attribute accepting an object.
As a bonus, the directive code will be simpler (as the object may be pass directly to the route).

[fzaninotto]

Switched to an object-based filter attribute, RFR again.

[yaoelvon]

very nice, this helps me! Thanks a lot.